Fix #202, fix variable name errors in tlmGUI

[ghost]

Describe the contribution
Fixed variable name errors that were missed in a previous conversion. The errors would not allow the generic telemetry page GUI to work.

Testing performed
Before the variables were renamed, opening a generic subsystem telemetry page would result in a python error:
NameError: name 'tlm_item_desc' is not defined

After the variables were renamed, the generic subsystem telemetry page comes up as it should, and displays telemetry from the cFS.

Expected behavior changes

• Or no impact to behavior

System(s) tested on

• Hardware: x86 PC and VM
• OS: Ubuntu 18.04 and Ubuntu 20.04
• Versions: cFS-GroundSystem v3.0.0-rc4+dev7 (main branch)

Additional context
None

Third party code
N/A

Contributor Info - All information REQUIRED for consideration of pull request
Alan Cudmore / NASA Goddard Space Flight Center

[skliper]

@astrogeco @acudmore - what's the status on this? Missing documentation as to why CCB:Ready was removed or what the path to closure is.

[astrogeco]

We renamed in the wrong "direction" so we ended up dropping it from the CCB agenda.

[skliper]

Added ignore label until this is fixed to update in the right direction or is closed/replaced.